"""
Copyright (C) 2014, 申瑞珉 (Ruimin Shen)

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
"""

from mpi4py import MPI


class MPICaller:
    def __init__(self):
        self.comm = MPI.COMM_WORLD
        self.rank = self.comm.Get_rank()
        self.size = self.comm.Get_size()
        self.count = 0

    def __call__(self, fn, *args, **kwargs):
        if self.count % self.size == self.rank:
            return fn(*args, **kwargs)
        self.count += 1
